CN107110933B

CN107110933B - Automatic configuration of low-field magnetic resonance imaging system

Info

Publication number: CN107110933B
Application number: CN201580055003.8A
Authority: CN
Inventors: 乔纳森·M·罗思伯格; 杰里米·克里斯托弗·乔丹; 迈克尔·斯蒂芬·普尔; 劳拉·萨科利克; 托德·雷亚里克; 格雷戈里·L·哈尔瓦特
Original assignee: Hyperfine Research Inc
Current assignee: Hepperfina Co ltd
Priority date: 2014-09-05
Filing date: 2015-09-04
Publication date: 2020-09-04
Anticipated expiration: 2035-09-04
Also published as: CA2960194A1; US20160069968A1; US20160069975A1; MX366786B; CN107110931B; US20220091211A1; CA2960189A1; US9625543B2; US10241177B2; AU2015311749A1; WO2016037042A1; US9817093B2; US20220043088A1; US20160231402A1; US20160231399A1; US10145922B2; JP2020121137A; CN112083365B; JP2020127750A; JP2017527425A

Abstract

In some aspects, a method of operating a magnetic resonance imaging system comprising B₀A magnet and a magnet configured to be driven from B during operation₀At least one thermal management component that the magnet transfers heat away. The method comprises the steps of₀The magnet provides operating power, monitor B₀Temperature of magnet to determine B₀A current temperature of the magnet, and operating the at least one thermal management component below an operational capacity in response to an occurrence of the at least one event.

Description

Automatic configuration of low-field magnetic resonance imaging system

Background

Magnetic Resonance Imaging (MRI) provides an important imaging modality for many applications and is widely used in clinical and research environments to produce images of the interior of the human body. As a general rule, MRI is based on detecting Magnetic Resonance (MR) signals, which are electromagnetic waves emitted by atoms in response to state changes caused by an applied electromagnetic field. For example, Nuclear Magnetic Resonance (NMR) techniques include: MR signals emitted from nuclei of excited atoms are detected upon realignment or relaxation of nuclear spins of atoms in an object being imaged (e.g., atoms in human tissue). The detected MR signals may be processed to generate images, which in the context of medical applications allow investigation of internal structures and/or biological processes within the body for diagnostic, therapeutic and/or research purposes.

MRI offers an attractive imaging modality for biological imaging due to the ability to produce non-invasive images with relatively high resolution and contrast without the safety concerns of other modalities (e.g., without the need to expose the subject to ionizing radiation such as x-rays or introduce radioactive substances into the body). In addition, MRI is particularly well suited to provide soft tissue contrast, which may be used to image subject objects that other imaging modalities cannot satisfactorily image. Furthermore, MR techniques are capable of capturing information about structures and/or biological processes that cannot be acquired by other modalities. However, MRI suffers from a number of drawbacks, which may involve relatively high cost of equipment, limited availability and/or difficulty in gaining access to a clinical MRI scanner and/or the length of the image acquisition process for a given imaging application.

The trend in clinical MRI is to increase the field strength of MRI scanners to improve one or more of scan time, image resolution, and image contrast, which in turn continues to increase costs. Most installed MRI scanners operate at 1.5 or 3 tesla (T), which refers to the main magnetic field B₀Of the field strength of (a). Clinical MRI scanThe rough cost of instruments is estimated to be approximately one million dollars per tesla, which does not account for the substantial operating, service, and maintenance costs involved in operating such MRI scanners.

In addition, conventional high-field MRI systems typically require large superconducting magnets and associated electronics to generate a strong, uniform static magnetic field (B) in which an object (e.g., a patient) is imaged₀). The size of such systems is considerable, with typical MRI equipment including multiple rooms for magnets, electronics, thermal management systems, and console areas. The size and expense of MRI systems often limits their use to facilities such as hospitals and academic research centers that have sufficient space and resources to purchase and maintain them. The high cost and large space requirements of high-field MRI systems result in limited availability of MRI scanners. Thus, as discussed in further detail below, the following clinical situations often exist: MRI scanning would be beneficial but not practical or feasible due to one or more of the limitations described above.

Disclosure of Invention

Low-field MRI offers an attractive imaging solution, offering a relatively low-cost, high-availability alternative to high-field MRI. The inventors have recognized that the characteristics of low-field MRI facilitate the implementation of substantially smaller and/or more flexible devices that can be deployed in various environments and facilities, and also allow the development of portable or transportable low-field MRI systems. Because such systems may operate in different environments at different times and/or because such systems may operate in generally uncontrolled environments (e.g., low-field MRI systems may operate outside of a specially shielded room in which high-field MRI systems typically operate), it may be advantageous to provide "on-site" and/or dynamic calibration of one or more components of the MRI system to adjust or optimize the system for the environment in which the system is located. According to some embodiments, as will be discussed in further detail below, automated techniques are provided to modify or adjust one or more aspects of an MRI system based on the environmental and/or operating conditions of the system. According to some embodiments, automated techniques are provided that facilitate easy access to low-field MRI systems, thereby enabling use by users/operators with a wider range of training and/or expertise (including users/operators who are not trained professionally or who have little or no expertise).

Some embodiments include a method of operating a magnetic resonance imaging system comprising B₀A magnet and a magnet configured to be driven from B during operation₀At least one thermal management component that the magnet transfers heat away, the method comprising: to B₀The magnet provides operating power; monitoring B₀Temperature of magnet to determine B₀The current temperature of the magnet; and operating at least one thermal management component at less than operational capacity in response to the occurrence of the at least one event.

Some embodiments include a magnetic resonance imaging system comprising: b is₀A magnet configured to provide B₀At least a portion of a field; at least one thermal management component configured to be driven from B during operation₀The magnet transfers heat away; and at least one processor programmed to monitor B₀Temperature of magnet to determine B₀The current temperature of the magnet and, in response to the occurrence of the at least one event, operating the at least one thermal management component below an operational capacity.

Some embodiments include a method of dynamically adjusting B produced by a magnetic resonance imaging system₀A method of fields, the method comprising: detecting the formation of a structural change in the structural change of the structural change₀Contribution of magnet generation to B₀A first magnetic field of the field; and selectively operating at least one shim coil (shim coil) based on the detected first magnetic field to produce a second magnetic field to adjust B produced by the magnetic resonance imaging system₀A field.

Some embodiments include a magnetic resonance imaging system comprising: is configured to provide a contribution to B₀B of a first magnetic field of the field₀A magnet; a plurality of shim coils; at least one sensor arranged to act as B₀Detecting a first magnetic field while the magnet is operating; and at least one controller configured to selectively based on the first magnetic field detected by the at least one sensorOperating at least one of the plurality of shim coils to generate a second magnetic field to adjust B generated by the magnetic resonance imaging system₀A field.

Some embodiments include a method of degaussing a subject object in a vicinity of a magnetic resonance imaging system including a magnetic resonance imaging system configured to provide, at least in part, B₀B of the field₀A magnet, the method comprising: operating B with a first polarity₀A magnet; and periodically operating B with a second polarity opposite to the first polarity₀A magnet.

Some embodiments include a magnetic resonance imaging system configured to degauss a nearby subject object, the magnetic resonance imaging system comprising: b is₀A magnet configured to at least partially provide B₀A field; and a controller configured to: operating B with a first polarity₀A magnet; and periodically operating B with a second polarity opposite to the first polarity₀A magnet.

Some embodiments include a method of dynamically configuring a magnetic resonance imaging system for use in an arbitrary environment, the method comprising: identifying at least one obstruction to performing magnetic resonance imaging; and automatically performing at least one remedial action based at least in part on the identified at least one obstacle.

Some embodiments include a method of configuring a magnetic resonance imaging system having components capable of being operably coupled with different types of radio frequency coils, the method comprising: detecting whether a radio frequency coil is operatively coupled to a component of a magnetic resonance imaging system; determining information about the radio frequency coil in response to determining that the radio frequency coil is operatively coupled to the magnetic resonance imaging system; and automatically performing at least one action to configure the magnetic resonance imaging system to operate with the radio frequency coil based at least in part on the information about the radio frequency coil.

Some embodiments include a magnetic resonance imaging system comprising: b is₀A magnet configured to provide B₀At least a portion of a field; a component capable of being operably coupled with different types of radio frequency coils; and at leastA controller configured to: detecting whether a radio frequency coil is operatively coupled to a component of a magnetic resonance imaging system; determining information about the radio frequency coil in response to determining that the radio frequency coil is operatively coupled to the magnetic resonance imaging system; and automatically performing at least one action to configure the magnetic resonance imaging system to operate with the radio frequency coil based at least in part on the information about the radio frequency coil.

Some embodiments include a method of operating a low-field magnetic resonance imaging system including at least one communication interface that allows the magnetic resonance imaging system to communicate with one or more external computing devices, the method comprising: initiating, by at least one processor of a low-field magnetic resonance imaging system, a connection with at least one external computing device; and exchanging, using the at least one processor, information with the at least one external computing device.

Some embodiments include a low-field magnetic resonance imaging system, comprising: at least one magnetic component configured to operate at a low field; at least one communication interface that allows the low-field magnetic resonance imaging system to communicate with one or more external computer devices; and at least one processor configured to initiate a connection with the at least one external computing device and exchange information with the at least one external computing device using the at least one processor.

Some embodiments include a method of assisting in automatic setup of a magnetic resonance imaging system, the method comprising: detecting a type of radio frequency coil connected to the magnetic resonance imaging system and/or a position of the patient support; and automatically performing at least one setup procedure based at least in part on the detected type of radio frequency coil and/or the position of the patient support.

Drawings

Various aspects and embodiments of the disclosed technology will be described with reference to the following drawings. It should be understood that the drawings are not necessarily drawn to scale.

FIG. 1 is a schematic diagram of a low-field MRI system that may be automatically configured according to the techniques described herein;

fig. 2A and 2B are illustrations of a portable low-field MRI system according to some embodiments;

fig. 2C and 2D are illustrations of a transportable low-field MRI system, according to some embodiments;

FIG. 3 is a flow diagram of a process for automatically configuring a low-field MRI system, according to some embodiments;

FIG. 4 is a flow diagram of a process for powering on a low-field MRI system, according to some embodiments; and

FIG. 5 is a schematic diagram of a networked environment, where some techniques described herein may be performed.

Detailed Description

The MRI scanner market is dominated by high field systems for the most part and is dedicated to medical or clinical MRI applications. As mentioned above, the general trend in medical imaging is to produce MRI scanners with increasingly greater field strengths, with the vast majority of clinical MRI scanners operating at 1.5T or 3T, while higher field strengths of 7T and 9T are used in research environments. As used herein, "high field" refers generally to MRI systems currently used in clinical settings, and more specifically to main magnetic fields (i.e., B) at 1.5T or above₀Field), whereas clinical systems operating between 0.5T and 1.5T are also generally considered "high field". In contrast, "low field" generally refers to B at less than or equal to about 0.2T₀A field operated MRI system. The attractiveness of high-field MRI systems includes increased resolution and/or reduced scan time compared to low-field systems, thereby facilitating the push for increasingly higher field strengths for clinical and medical MRI applications.

The inventors have developed techniques for producing improved quality portable and/or low cost low field MRI systems that can improve the large scale deployment of MRI technology in a variety of environments, including but not limited to installation at hospitals and research facilities. For example, in addition to hospitals and research facilities, low-field MRI systems may be deployed as permanent or semi-permanent devices in offices, clinics, multiple departments within a hospital (e.g., emergency rooms, operating rooms, radiology departments, etc.), or as mobile/portable/transportable systems that can be transported to a desired location.

The inventors have recognized that the widespread deployment of such low-field MRI systems presents challenges in ensuring that the MRI system performs properly in any environment in which the system operates. Manually configuring the parameters of a low-field MRI system for a particular environment and/or application is cumbersome and typically requires technical expertise that may not be available to an ordinary user of the low-field MRI system. In addition, the attributes of the environment that are important to the operation of the system cannot be determined or otherwise obtained by a human operator.

Accordingly, some embodiments relate to techniques for automatically configuring a low-field MRI system based at least in part on environmental and/or operating conditions of the low-field MRI system. As will be discussed in more detail below, the techniques for automatically configuring may be performed upon powering up the system or at any other suitable time in response to detecting one or more changes in environmental and/or operating conditions. Some aspects relate to an automatic setup process for a low-field MRI system in which component(s) of the system are automatically configured based at least in part on the environmental and/or operating conditions in which the low-field MRI system operates. Some aspects relate to dynamically configuring an MRI system in view of changes in environmental and/or operating conditions. Some aspects or techniques relate to automated techniques for adjusting operation of a system based on an operating mode of the system (e.g., low power mode, heating, idle, etc.).

Furthermore, as mentioned above, increasing the field strength of MRI systems results in increasingly expensive and complex MRI scanners, thus limiting usability and preventing their use as a general and/or commonly available imaging solution. The relatively high cost, complexity and size of high-field MRI have primarily limited their use to dedicated facilities. Furthermore, conventional high-field MRI systems are typically operated by technicians that have extensive training on the system to be able to produce the desired images. The requirement that there be a trained technician to operate a high-field MRI system further results in limiting the availability of high-field MRI and the inability of high-field MRI to be used as a widely available and/or versatile imaging solution.

The inventors have recognized that ease of use can be a substantial contributor to enabling a low-field MRI system to be widely available, deployed, and/or used in a variety of situations and environments. To this end, the inventors have developed automatic, semi-automatic, and/or assisted setup techniques that facilitate simple and intuitive use of low-field MRI systems. Thus, the amount of training required to operate such low-field MRI systems may be substantially reduced, increasing the instances in which low-field MRI systems may be employed to perform desired imaging applications.

Following are more detailed descriptions of various concepts of methods and apparatus for low-field magnetic resonance applications, including low-field MRI, and embodiments thereof. It should be appreciated that the various aspects described herein may be implemented in any of numerous ways. Examples of specific implementations are provided herein for illustrative purposes only. In addition, the various aspects described in the following embodiments may be used alone or in any combination and are not limited to the combinations explicitly described herein. While some of the techniques described herein are designed to address, at least in part, the challenges associated with low-field and/or portable MRI, the techniques are not limited in this regard and may be applied to high-field MRI systems, as these aspects are not limited to use with any particular type of MRI system.

Fig. 1 is a block diagram of exemplary components of a low-field MRI system 100. In the illustrative example of fig. 1, the low-field MRI system 100 includes a workstation 104, a controller 106, a pulse sequence repository 108, a power management system 110, and a magnetic component 120. It should be understood that the system 100 is illustrative and that the low-field MRI system may have one or more other components of any suitable type in addition to or in place of the components shown in fig. 1.

As shown in fig. 1, the magnetic components 120 include a magnet 122, shim coils 124, RF transmit/receive coils 126, and gradient coils 128. The magnet 122 may be used to generate a main magnetic field B₀. The magnet 122 may be any suitable type of magnet capable of generating a main magnetic field having a low field strength (i.e., a magnetic field having a strength of 0.2 tesla or less). Shim coils 124 may be used to contribute magnetic field(s) to improve B produced by the magnet 122₀Uniformity of the field. The gradient coils 128 may be arranged to provide a gradient field and may, for example, be arranged to produce gradients in the magnetic field in three substantially orthogonal directions (X, Y, Z).

The RF transmit/receive coil 126 includes a coil that can be used to generate RF pulses to induce an oscillating magnetic field B₁The one or more transmit coils of (a). The transmit coil(s) may be configured to generate any suitable type of RF pulses that may be used to perform low-field MR imaging. In some embodiments, as will be discussed in more detail below, a suitable type of RF pulse that may be used to perform low-field MR imaging may be selected based at least in part on environmental conditions.

Each of the magnetic components 120 may be configured in any suitable manner. For example, in some implementations, one or more of the magnetic components 120 may be fabricated using techniques described in the following applications: U.S. application co-filed with attorney docket No. O0354.70000US01, entitled Low Field Magnetic Resonance Imaging Methods and Apparatus, filed on 9, 4/2015, the entire contents of which are incorporated herein by reference.

The power management system 110 includes electronics that provide operating power to one or more components of the low-field MRI system 100. For example, as will be discussed in more detail below, the power management system 110 may include one or more power supplies, gradient power amplifiers, transmit coil amplifiers, and/or any other suitable power electronics needed to provide suitable operating power to turn on and operate the components of the low-field MRI system 100.

As shown in fig. 1, the power management system 110 includes a power supply 112, an amplifier(s) 114, a transmit/receive switch 116, and a thermal management component 118. The power supply 112 includes electronics that provide operating power to the magnetic components 120 of the low-field MRI system 100. For example, the power supply 112 may include one or more B₀Coil (e.g. B)₀Magnet 122) provides the electronics that operate the electrical power to generate the main magnetic field of the low-field MRI system. In some embodiments, power supply 112 is a single-pole Continuous Wave (CW) power supply, however, any power supply may be usedA suitable power supply. The transmit/receive switch 116 may be used to select whether the RF transmit coil or the RF receive coil is operating.

The amplifier(s) 114 may include one or more RF receive (Rx) preamplifiers that amplify MR signals detected by one or more RF receive coils (e.g., coil 124), one or more RF transmit (Tx) amplifiers configured to provide power to one or more RF transmit coils (e.g., coil 126), one or more gradient power amplifiers configured to provide power to one or more gradient coils (e.g., gradient coil 128), and shim amplifiers configured to provide power to one or more shim coils (e.g., shim coil 124).

The thermal management component 118 provides cooling for the components of the low-field MRI system 100 and may be configured to cool by facilitating the transfer of thermal energy generated by one or more components of the low-field MRI system 100 away from these components. Thermal management component 118 may include, but is not limited to, components that perform water-based or air-based cooling that may be associated with MRI components that generate heat (including, but not limited to, B)₀Coils, gradient coils, shim coils, and/or transmit/receive coils) are integrated together or disposed proximate to the MRI components. Thermal management component 118 may include any suitable heat transfer medium (including, but not limited to, air and water) to transfer heat away from components of low-field MRI system 100. The thermal management component may be, for example, any of the thermal management components and/or techniques described in the following applications: a U.S. application filed concurrently with attorney docket No. O0354.70004US01, entitled "thermal management Methods and Apparatus," filed on 9, 4, 2015, the entire contents of which are incorporated herein by reference.

As shown in fig. 1, the low-field MRI system 100 includes a controller 106 (also referred to herein as a "console") having control electronics that send instructions to the power management system 110 and receive information from the power management system 110. The controller 106 may be configured to implement one or more pulse sequences for determining instructions sent to the power management system 110 to operate one or more of the magnetic components 120 in a desired sequence. The controller 106 may be implemented as hardware, software, or any suitable combination of hardware and software, as the aspects of the disclosure provided herein are not limited in this respect.

In some embodiments, the controller 106 may be configured to implement the pulse sequences by obtaining information about the pulse sequences from a pulse sequence repository 108, the pulse sequence repository 108 storing information about each of the one or more pulse sequences. The information stored by the pulse sequence repository 108 about a particular pulse sequence may be any suitable information that enables the controller 106 to implement a particular pulse sequence. For example, the information about the pulse sequence stored in the pulse sequence repository 108 may include one or more parameters for operating the magnetic component 120 according to the pulse sequence (e.g., parameters for operating the RF transmit/receive coil 126, parameters for operating the gradient coil 128, etc.), one or more parameters for operating the power management system 110 according to the pulse sequence, one or more programs including instructions that, when executed by the controller 106, cause the controller 106 to control the system 100 to operate according to the pulse sequence, and/or any other suitable information. The information stored in the pulse sequence repository 108 may be stored on one or more non-transitory storage media.

As shown in fig. 1, the controller 106 also interacts with the computing device 104 programmed to process the received MR data. For example, the computing device 104 may process the received MR data to generate one or more MR images using any suitable image reconstruction process (es). The controller 106 may provide information regarding the one or more pulse sequences to the computing device 104 to facilitate processing of the MR data by the computing device. For example, the controller 106 may provide information regarding one or more pulse sequences to the computing device 104, and the computing device may perform an image reconstruction process based at least in part on the provided information.

The computing device 104 may be any electronic device configured to process acquired MR data and generate one or more images of the subject being imaged. In some implementations, the computing device 104 can be a stationary electronic device such as a desktop computer, a server, a rack-mounted computer, or any other suitable stationary electronic device that can be configured to process MR data and generate one or more images of the subject being imaged. Alternatively, the computing device 104 may be a portable device such as a smartphone, personal digital assistant, laptop computer, tablet computer, or any other portable device that may be configured to process MR data and generate one or more images being imaged. In some implementations, computing device 104 may include a plurality of any suitable types of computing devices, as aspects provided herein are not limited in this respect. The user 102 may interact with the computing device 104 to control various aspects of the low-field MR system 100 (e.g., program the system 100 to operate according to a particular pulse sequence, adjust one or more parameters of the system 100, etc.) and/or view images obtained by the low-field MR system 100.

Fig. 2A and 2B illustrate a portable or transportable low-field MRI system 200 according to some embodiments. The system 200 may include one or more of the components described above in connection with fig. 1. For example, the system 200 may include magnetic and power components, and possibly other components (e.g., thermal management, console, etc.), arranged together on a single, generally transportable and deformable structure. The system 200 can be designed to have at least two configurations: a configuration suitable for transport and storage and a configuration suitable for handling. Fig. 2A shows system 200 when secured for transport and/or storage, while fig. 2B shows system 200 when transformed for operation. System 200 includes a portion 290A that can be slid into portion 290B and pulled out of portion 290B when the system is transformed from its transport configuration to its operating configuration, as indicated by the arrow shown in fig. 2B. Portion 290A may house power electronics 110, console 106 (which may include an interface device such as the touch panel display shown in fig. 2A and 2B), and thermal management 118. Portion 290A may also include other components for operating system 200 as desired.

The portion 290B includes the magnetic components 120 of the low-field MRI system 200, including the

laminates

210A and 210B on which one or more magnetic components (e.g., the magnet 112, the shim coils 124, the RF transmit/receive coils 126, the gradient coils 128) are integrated in any combination. When deformed into a configuration suitable for operating the system to perform MRI (as shown in FIG. 2B), the support surfaces of

portions

290A and 290B provide a surface on which a subject to be imaged may lie. A slidable surface 265 may be provided to facilitate sliding the object into position such that a portion of the object is within the field of view of the laminate providing the corresponding low-field MRI magnet. System 200 provides a portable, compact configuration of a low-field MRI system that facilitates MRI imaging in situations where conventional access is not available (e.g., in an emergency room).

Fig. 2C and 2D illustrate another generally transportable low-field MRI system according to some embodiments. Fig. 2C illustrates an example of a foldable low-field MRI system 280 utilizing a bi-planar hybrid magnet, according to some embodiments. In fig. 2C, the collapsible system is in a collapsed configuration that facilitates transport of the system or storage system when not in use. The foldable system 280 comprises: a slidable bed 284 configured to support a human patient and allow the patient to slide in and out of the imaging region between

housings

286A and 286B in the direction of arrow 2281. The

housings

286A and 286B house the magnetic components of the foldable system 280 to generate magnetic fields for performing MRI. According to some embodiments, the magnetic component may be produced, manufactured and arranged using only lamination techniques, using only conventional techniques, or using a combination of both (e.g., using hybrid techniques).

Fig. 2D shows the foldable system 280 unfolded and with the patient on the slidable bed 284 before being inserted between the

housings

286A and 286B to be imaged. According to some embodiments, each of the

shells

286A and 286B houses a hybrid magnet coupled with the thermal management component to draw heat away from the magnetic component. Specifically, each of the

housings

286A and 286B on the opposite sides of the imaging area includes B therein₀ Coils 205a and 205B, laminate 210 (210B of laminate 210 is visible in housing 286B in a face-up arrangement) And is arranged at B₀Thermal management features 230 between the coils. The magnetic components housed in 286A and 286B may be substantially identical to form a symmetric bi-planar hybrid magnet, or the magnetic components housed in 286A and 286B may be different to form an asymmetric bi-planar hybrid magnet, as these aspects are not limited for use with any particular design or configuration of hybrid magnet.

In accordance with the techniques described herein, one or more components of a low-field MRI system (e.g.,

systems

100, 200, and/or 280) are automatically configured to ensure that the system will perform or is performing properly during operation. As described above, such an MRI system may operate in various environments: the environment requires one or more parameters of the system to be adjusted to ensure satisfactory operation in a given environment. As also described above, manual configuration of components of a low-field MRI system is cumbersome and requires expertise that many users of MRI systems may not have. In many cases, the environmental and/or operating conditions to which the system needs to adjust or adapt are not determinable to a human operator (e.g., radio frequency noise or other electromagnetic interference (EMI), inadvertent short or open circuits, misaligned components, etc.), such that proper adjustment of the system is not possible even for an expert. Accordingly, some embodiments are configured to automatically perform a set of configuration and/or setup operations in response to the occurrence of a particular event (e.g., powering on a low-field MRI system, waking from a sleep mode or low-power mode, detection of changing environmental conditions, etc.).

FIG. 3 illustrates an auto-configuration process that may be performed in response to the occurrence of an event, according to some embodiments. It should be understood that although fig. 3 illustrates a number of configuration or setup operations that may be performed, any one or combination of these operations may be performed, as these aspects are not limited in this respect. Additionally, while the exemplary configuration operations shown in FIG. 3 are shown as being performed serially, it should be understood that one or more of the configuration operations may be performed partially or completely in parallel, and that there is no limitation on which particular configuration operations are performed and/or when.

In act 310, the low-field MRI system is powered on. FIG. 4 illustrates a power-up process that may be performed in act 310, according to some embodiments. It should be understood that although FIG. 4 illustrates a plurality of power-on operations that may be performed, any one or combination of these operations may be performed, as these aspects are not limited in this respect. Additionally, while the exemplary configuration operations shown in FIG. 4 are shown as being performed serially, it should be understood that one or more of the configuration operations may be performed partially or completely in parallel, and that there is no limitation on which particular configuration operations are performed and/or when.

In act 410, the low-field MRI system is connected to a power source. For example, the low-field MRI system may be connected to a standard wall outlet, to an external power source, such as a generator, or to any other suitable type of power source for providing operating power to the components of the low-field MRI system. In act 412, it is verified that the emergency power down is operational. Patient safety is a primary consideration in designing medical devices. Thus, some low-field MRI systems used in accordance with the techniques described herein include an emergency power-off that may be triggered manually or automatically in situations where patient safety is a concern (e.g., magnet overheating). Thus, to ensure safe operation, the system may check to confirm that any and all power cuts (or other safety mechanisms) are enabled and/or operable.

In act 414, the console 104 is powered on, for example, by the user pressing a power switch, button, or other mechanism on the console. In response to being powered on, the console may perform a plurality of boot processes prior to running (launch) a control application for controlling one or more operations of the low-field MRI system. After or during the performance of any boot processes, a control application configured to control one or more operations of the low-field MRI system is run on the console (act 416). As will be discussed in more detail below, the control application may run automatically upon powering up the console or in response to user interaction with the console or an external electronic device configured to interact with the console. In response to running the control application, the application may instruct the console to perform one or more operations, including but not limited to instructing the power supply 112 to turn on system DC power.

After or during the running of the control application, other components of the low-field MRI system may be enabled and/or configured. For example, in act 418, the control application may instruct the power supply 112 to obtain B by heating the magnet therein₀The field is suitable for imaging, for example, to energize the magnet 122 at temperatures to perform low-field MRI. In some implementations, the process of heating the magnet may require a significant amount of time (e.g., 30 minutes) to provide a stable B suitable for imaging₀A field. To reduce the amount of time required to heat the magnet 122, some embodiments perform one or more "preheat" operations. For example, one or more of the thermal management components 118 that transfer heat away from the magnetic components 120 of the low-field MRI system during operation of the low-field MRI system may be turned down or off to cause the magnet to heat up faster than when the thermal management components are operating normally. In some implementations, the thermal management component 118 includes an air or water cooling system (e.g., a fan and/or pump) to provide cooling of the magnetic components of the low-field MRI system. During preheating of the magnet, the fan and/or pump may be turned off or down (e.g., by reducing cooling capacity or intensity) to speed up the magnet heating process. Operating one or more thermal management components at less than operational capacity refers herein to intentionally tuning one or more thermal management components, including by not operating one or more thermal management components at all, such that the ability to remove heat is reduced compared to its normal operation.

In embodiments that modify the operation of the thermal management component 118, the temperature of the magnet should be closely monitored to ensure that the magnet does not overheat and/or to determine when to turn on the thermal management component or to increase the ability/strength of the thermal management component. The temperature of the magnet may be determined in any suitable manner, including but not limited to using a temperature sensor, determining the temperature of the magnet based at least in part on a measured voltage of the magnet, and the like. According to some embodiments, automatic control of thermal management is provided with temperature sensing (e.g., via sensors and/or voltage measurements) to accelerate heating and approach thermal equilibrium or appropriate B at the magnet₀When the field is stableCooling and/or increasing the cooling intensity.

Some embodiments include a low power mode for use when the system is idle (e.g., not being used for imaging) to keep the magnet warm. For example, in the low power mode, less current may be provided to the magnet while still enabling the magnet 112 to remain at an acceptable temperature for imaging. The low power mode may be implemented in any suitable manner that enables the magnet to be maintained at a desired temperature. For example, one or more of the techniques described above for reducing the heating time of the magnet (e.g., turning off or turning down one or more thermal management components) may also be used to place the low-field MRI system in a low-power mode. Thus, when not in use, the magnet can be kept warm with less power so that when needed, the magnet is ready without a heating period. In some implementations, operation in the low power mode may be initiated automatically when the low-field MRI system 100 has not been operating for a particular amount of time and/or the low power mode may be initiated manually via a switch, button, or other interface mechanism provided by the system.

Alternatively, the low power mode may be used in response to determining that an ambient temperature of an environment in which the low-field MRI system 100 is operating is above a certain temperature. For example, if a low-field MRI system is deployed in a high temperature environment (e.g., a desert), the magnet may not be able to operate in the normal operating mode due to the possibility of the magnet overheating. However, in this case, the MRI system 100 can still operate in the low power mode by driving the magnet with less current than that used in an environment having a lower temperature. Thus, this low power mode enables the use of low-field MRI systems in challenging environments that are generally not suitable for MRI system operation.

In some embodiments, the time required for magnet heating prior to imaging can be reduced by determining and compensating for fluctuations in low-field MRI parameters during the heating process to achieve imaging before the fluctuations have stabilized. For example, B₀The larmor frequency of a magnet typically fluctuates as the magnet heats up and becomes stable. Some embodiments characterize how the larmor frequency tracks the voltage (or temperature) of the magnet) And compensates for the change in frequency to allow imaging before the magnet reaches its normal operating temperature. B is₀The uniformity of the field is another parameter known to fluctuate during heating of the magnet. Thus, some embodiments feature B₀How the field uniformity tracks the voltage (or temperature) of the magnet, and compensates for changes in the field uniformity (e.g., using one or more shim coils) to enable imaging before the field uniformity reaches a normal operating level. Other low-field MRI parameters that fluctuate during heating of the magnet 112 may also be tracked and compensated for imaging with the low-field MRI system before the magnet reaches thermal equilibrium and/or field stability, provided that fluctuations in these parameters can be characterized by measuring the voltage (or temperature) of the magnet or some other parameter of the low-field MRI system.

Returning to the process of FIG. 4, in act 420, the gradient coils are enabled. The inventors have recognized that in some embodiments, the process of enabling the gradient coils may be delayed until shortly before being ready for imaging to reduce the power consumption of the low-field MRI system. After the low-field MRI system is operational, act 422 may be performed to monitor one or more properties of the magnet to ensure that the magnet remains in a state suitable for operation. One or more remedial actions may be performed if it is detected that one or more properties of the magnet have drifted or otherwise changed in a manner that affects the ability to obtain a satisfactory image.

Returning to the process of fig. 3, in act 312, one or more conventional system checks are performed to ensure proper operation of the low-field MRI system 100. For example, a conventional system check may include checking whether the magnet 112 is shorted or open. Shorting of the magnet 112 may occur for any of a variety of reasons. For example, thermal contraction and expansion (thermal cycling) of various components of the low-field MRI system during normal operational use and/or due to operation in different environments may result in shorting of the magnet 112 or a portion thereof or shorting of any of the various other circuits, coils, etc. of the MRI system. For example, thermal cycling may otherwise cause the isolated conductive material to contact the short circuit of the system (e.g., the windings in the coil). For example, in some cases, an electrically conductive (e.g., aluminum) surface of a cooling plate included as a component of thermal management system 118 may contact the electrically conductive material of one or more coils being cooled to cause the coils to short circuit. Some embodiments test the system (e.g., magnet 112) to determine if there is a short circuit, and if so, may provide an alert to the user that the system is inoperable and requires servicing. A short circuit may be detected by monitoring a current-voltage (IV) curve resulting from powering one or more components to assess whether the IV curve responds as expected or by using any other suitable technique.

According to some embodiments, the system detects an open circuit. For example, many factors can cause the magnet 112 (or any other system circuit) to open, thereby not allowing current to flow. Open circuits may be caused by thermal cycling and/or during use of the system, for example, by separating electrical connections or by loosening components (e.g., displacement of bolts or screws used to connect components of the low-field MRI system 100). For example, thermal cycling of the magnet can cause bolts/screws in the magnet assembly to loosen, which can result in magnet open circuits. Some embodiments test the magnet 112 to determine if it is open circuit (e.g., by observing whether the applied voltage draws current), and if open circuit, an alert may be provided to the user that the magnet is inoperable and requires servicing.

Other conventional system checks that may be performed according to some embodiments include determining the stability of the power supply 112. The inventors have recognized that in some implementations, the power supply 112 may operate near the edge of stability, and small deviations outside this range may cause the power supply to become unstable and oscillate. The power supply 112 may also oscillate for other reasons including, but not limited to, a circuit failure within the power supply. The stability of the power supply may be determined in any suitable manner, including but not limited to measuring the current drawn from the power supply to ensure that the current being drawn is as expected.

The inventors have recognized that the quality of the power supply used to power the low-field MRI system 100 may vary depending on the environment in which the low-field MRI system is deployed. For example, a low-field MRI system operating in the field may be powered by, for example, a generator, which may present power challenges that are not present when powering a low-field MRI system using a standard power outlet in a hospital. As another example, power quality may vary with the operation of other devices on the same local power grid. As yet another example, a low-field MRI system deployed in a mobile environment, such as an ambulance, may need to be powered via a battery and a converter. To address these issues, some embodiments perform a conventional system check to evaluate the characteristics of the power supply in any suitable manner to determine whether the power supply is of sufficient quality to operate the system.

As another example, a low-field MRI system may be deployed in a non-standard environment where the quality and/or standard of the power hook-up device may not be known. To address this issue, some embodiments include checking the wiring of the power outlet to determine if the outlet is properly wired before trusting the power source to power the system to avoid the power source damaging components of the system. Checking the wiring of the power outlet may include, but is not limited to, measuring the voltage from the power outlet, measuring the noise level in the current provided by the power outlet, and/or determining whether the power outlet is properly wired (e.g., live, neutral, and ground are all at appropriate values). The inventors have recognized that the power generated by some power sources (e.g., generators or power inverters) can be noisy. If it is determined that the power outlet is not properly wired or has an unacceptable level of noise, a user of the system may be notified and an alternate power source may be sought before powering on the low-field MRI system.

The inventors have recognized that external sources of electromagnetic noise can affect the ability of a low-field MRI system to operate properly in various environments in which the system may be deployed. Returning to the process of fig. 3, in act 314, the external noise sources are evaluated to determine whether the detected noise source(s) can be properly addressed by modifying one or more operating parameters of the low-field MRI system, whether noise compensation techniques can be used to compensate for the noise sources, or whether the low-field MRI system will not operate properly in the presence of one or more detected noise sources, in which case the low-field MRI system should alert the operator that the system should be moved to another location that is less affected by noise.

According to some embodiments, environmental conditions (including but not limited to external temperature drift and/or system temperature drift) may be detected and/or monitored, and the carrier frequency (larmor frequency) of one or more pulse sequences used by the low-field MRI system for imaging may be modified to compensate for changes in environmental conditions. In addition to pulse sequence parameters, aspects of the low-field MRI system may additionally or alternatively be adjusted or modified to compensate for changes in environmental conditions. For example, gradient currents or shim currents may also be determined based at least in part on the detected environmental conditions.

Some low-field MRI systems used in accordance with some embodiments may include a noise cancellation system configured to detect and at least partially compensate for external noise sources. For example, noise cancellation may be performed by providing an auxiliary receive channel to detect ambient Radio Frequency Interference (RFI). For example, one or more receive coils may be located at B₀The field of view of the field is near, rather than outside, to sample RFI without detecting MR signals emitted by the subject being imaged. RFI sampled by one or more auxiliary receive coils may be subtracted from signals received by one or more receive coils positioned to detect the transmitted MR signals. Such an arrangement has the ability to dynamically process and suppress RFI in order to provide a generally transportable and/or transportable low-field MRI system that is likely to be subject to different and/or varying levels of RFI depending on the environment in which the low-field MRI system is operating. Some examples of suitable noise cancellation techniques that may be used with low-field MRI systems are described in the following applications: U.S. application co-filed with attorney docket No. O0354.70001US01 entitled "Noise Suppression Methods and apparatus" filed on 9, 4, 2015, the entire contents of which are incorporated herein by reference.

Some embodiments may detect and compensate for noise sources using a multi-channel receive coil array configured to detect whether the spatial location of the received signal is located inside or outside the array. Signals determined to be from outside the array may be considered noise and may be subtracted from signals determined to be from inside the array. Noise cancellation techniques according to some embodiments include employing both a multi-channel receive coil array and one or more auxiliary coils for performing noise cancellation.

As another example, the noise cancellation system may detect whether there are nearby devices that produce electromagnetic noise that will affect the operation of the low-field MRI system, which will enable an operator of the low-field MRI system to determine whether the noise devices may be unplugged or removed prior to operation and/or any of a variety of noise cancellation techniques may be used to compensate for the noise introduced by the detected noise devices. External noise can come from several different types of sources that interfere with the ability of low-field MRI systems to produce images of acceptable quality. For example, a low-field MRI system may detect noise in a particular frequency band and configure the low-field MRI system to operate in different frequency ranges to avoid interference. As another example, a low-field MRI system may detect enough noise so that the system cannot avoid and/or sufficiently suppress the noise. For example, if the low-field MRI system is deployed near an AM broadcast station, it may be determined that the noise cancellation system is not capable of canceling broadcast noise, and a user of the low-field MRI system may be notified that the system should be moved to another location remote from the AM broadcast station to ensure proper operation of the low-field MRI system.

The inventors have recognized that external signals that can contribute to reduced performance of low-field MRI systems may include signals that are not generally considered conventional noise sources. For example, other low-field MRI systems operating in the vicinity of a given low-field MRI system being configured may also produce signals that may interfere with and negatively impact the performance of the low-field MRI system. According to some embodiments, a low-field MRI system is configured to detect other systems that are close enough to interfere with operation, and may communicate with any such systems to avoid interfering with each other. For example, multiple low-field MRI systems may be configured to communicate with each other using a network protocol (e.g., bluetooth, WiFi, etc.), and other low-field MRI systems operating in the vicinity of the low-field MRI system being configured may be identified by attempting to automatically connect to the other low-field MRI systems within range using the network protocol.

High-field MRI systems are deployed in specially shielded rooms to prevent electromagnetic interference from affecting the operation of the MRI system. Thus, the high-field MRI system is also isolated from external communications. Furthermore, due to the high field strength, the electronics are generally not in the B-position with the MRI system₀The magnets operate in the same room. On the other hand, low-field MRI systems may be configured to be generally portable and operate in locations other than specially shielded rooms. Accordingly, the low-field MRI system may be communicatively coupled to other devices, including other low-field MRI systems, in a manner that the high-field MRI system cannot, thereby achieving a number of benefits, some of which will be discussed in further detail below.

Fig. 5 illustrates a networked environment 500 in which one or more low-field MRI systems may operate. For example, multiple low-field MRI systems may be deployed in different rooms of a clinic or hospital, or may be deployed in different facilities that are remotely located. The systems may be configured to communicate via a network to identify the presence of other systems, and automatically configure the operating conditions of one or more low-field MRI systems with detection capabilities to reduce interference between the systems. As shown, the networked environment 500 includes a first low-field MRI system 510, a second low-field MRI system 520, and a third low-field MRI system 530. Each of the low-field MRI systems is configured with detection capabilities to discover the presence of the other low-field MRI systems via a network or using any other suitable mechanism (e.g., via device-to-device communication, detecting that the other low-field MRI system is a source of noise, etc.).

In some embodiments, a low-field MRI system may be configured to automatically detect the presence of another operating low-field MRI system by communicating directly with the other operating low-field MRI system. For example, low-field MRI systems may be configured to communicate with each other using a short-range wireless protocol (e.g., bluetooth, WiFi, Zigbee), and upon startup, the low-field MRI systems may attempt to discover whether there are any other low-field MRI systems operating nearby using the short-range wireless protocol.

In some implementations, the low-field MRI system may be configured to automatically detect the presence of another operating low-field MRI system using indirect techniques (i.e., by not directly communicating with the other low-field MRI system), for example, by communicating with a central computer, server (e.g., server 585), or an intermediary device configured to track the location of the system connected to the network. Any suitable indirect technique may be used. For example, in some embodiments, during operation, at startup and/or at some time after startup, the low-field MRI system may send one or more messages to the database 550 via the network 540 to register itself in the database. Registration of the low-field MRI system in database 550 may include providing any suitable information for storage in the database, including, but not limited to, an identifier of the low-field MRI system, an operating frequency of the system (e.g., larmor frequency), a location of the system, and an indication of whether the system is active or in a standby mode.

The information stored in the database 550 may be updated when the low-field MRI system is first started, when the low-field MRI system changes its operating state (e.g., transitions from an active mode to a standby mode), when the system changes one or more parameters (e.g., operating frequency), etc. At startup and/or at some time after startup, the low-field MRI system may send a query to a computer (e.g., server 585) associated with the database to determine whether additional low-field MRI systems are operating nearby and to obtain information about any detected low-field MRI systems. The query may include any suitable information that enables searching of database 550, including, but not limited to, an identifier of the low-field MRI system that issued the query and the location of the low-field MRI system. The low-field MRI system may then negotiate with other nearby systems, either directly or via a computer, to establish operating parameters so that the systems do not interfere with each other.

In other embodiments, detecting the presence of other nearby low-field MRI systems may be accomplished by measuring MR data. For example, the signals detected in response to the RF pulses may be analyzed to identify the presence of noise in the signals that characterizes the presence of a nearby low-field MRI system. Such embodiments do not require networked (direct or indirect) communication between multiple low-field MRI systems. However, the detection process requires data acquisition and data analysis, which can delay identifying nearby systems.

The inventors have recognized that in implementations where multiple low-field MRI systems are operating in close proximity, these systems may be configured to reduce interference between the systems or to reduce the impact of any other noise sources (e.g., AM radio stations) on the performance of the low-field MRI systems. For example, B of the first low-field MRI system may be adjusted₀The field is shifted to shift the larmor frequency of the system away from that of a nearby operating second low-field MRI system or away from any other frequency range in which noise is detected. The appropriate operating frequency and/or field strength (or any other suitable configuration parameters) to use may be established by direct negotiation between multiple low-field MRI systems or by communication with a central server responsible for resolving conflicts between systems. For example, a computer associated with database 550 may be responsible for assigning operational configuration parameters to a low-field MRI system located nearby.

The inventors have recognized that multiple low-field MRI systems may also benefit from being connected to each other using one or more networks by sharing information including, but not limited to, pulse sequences, waveform tables, pulse timing schedules, or any other suitable information. In some embodiments, potential conflicts between multiple low-field MRI systems may be managed through time-slicing operation of the systems to reduce interference effects between the systems. For example, a time sharing arrangement may be established between at least two low-field MRI systems to alternately or otherwise coordinate pulse sequences such that transmit and/or receive periods are appropriately staggered to reduce interference between the systems.

As shown, the networked environment may also include one or more Picture Archiving and Communication Systems (PACS)560, and the low-field MRI system may be configured to automatically detect and connect to the PACS 560 to enable storage of images captured with the low-field MRI system, to obtain one or more images (or information from one or more images) stored by the PACS 560, or to otherwise utilize information stored therein. The networked environment may also include a server 585 that can coordinate the activities of and/or between low-field MRI systems connected to the network. Server 585 may also be used to provide data, such as magnetic resonance fingerprinting data, to a low-field MRI system to enable MRI using MR fingerprinting. Server 585 may also operate as an information resource in other respects.

Returning to the process shown in fig. 3, in act 316, the mechanical configuration of the low-field MRI system is examined. For example, one or more of the mechanical components of the low-field MRI system may include a micro-switch, a sensor, or any other suitable device for determining whether one or more mechanical components are in the correct position. Examples of mechanical components of a low-field MRI system that may take measures to ensure their proper engagement include, but are not limited to, one or more RF coils (e.g., a head coil), a bed or table on which the patient is placed during imaging, and a disconnect device for the low-field MRI system when implemented as a portable system.

According to some embodiments, the exemplary system shown in fig. 2 may include the following components: the component enables different types of transmit/receive coils to be snapped into place, for example to transmit/receive coils configured to image different portions of the anatomy. In this way, a head coil, a chest coil, an arm coil, a leg coil, or any other coil configured for a particular portion of the anatomy may be snapped into the system to perform a corresponding imaging operation. The interface with the interchangeable coils (e.g., snap into place) may include a mechanism for detecting when the coils are properly attached, and this information may be communicated to an operator of the system. Alternatively or additionally, the transmit/receive coil may be configured with any suitable type of sensor capable of detecting when the coil is properly positioned and coupled to the system (e.g., snapped into place). According to some embodiments, as discussed in further detail below, the various transmit/receive coils may include a memory device and/or microcontroller that stores information about the coils (including, for example, any one or combination of coil type, operating requirements, field of view, number of channels), and/or any other information that may be useful to the system. The transmit/receive coil may be configured to automatically provide information (e.g., broadcast information) to the system when properly attached thereto, and/or the transmit/receive coil may be configured to provide any requested information in response to a query from the system. Any other components may be inspected to ensure that all relevant mechanical connections are made correctly, as these aspects are not limited in this respect.

According to some embodiments, the system may automatically select a scanning protocol based on the type of transmit/receive coil connected to the system. For example, if a head coil is detected as being connected, the system may automatically select an appropriate head imaging protocol. The system may provide a list of available head imaging protocols, which are then presented to the user for selection. Alternatively, if the system has additional information (e.g., information obtained from an RFID tag associated with the patient, as discussed in further detail below) or information from the patient scheduling system, the system may select a particular head imaging protocol and set the system to perform a corresponding imaging procedure (e.g., an imaging procedure to check for stroke). Similarly, when multiple protocols are presented and the user selects from the options, the system may set up the system to perform the corresponding imaging procedure. By way of example, the system may obtain (e.g., load or create) an appropriate pulse sequence(s), select an appropriate contrast type, select an appropriate field of view, prepare to acquire one or more scout images, and/or the like. It should be understood that whatever type of transmit/receive coil is detected, the system may present available protocols and/or prepare and set up the system to perform a selected or automatically identified scan protocol.

According to some embodiments, the system may automatically select a scanning protocol based on the location of one or more components of the system. For example, the system may detect the position of a patient support (e.g., a bed, table, or chair) and automatically select an appropriate imaging protocol or present a list of available imaging protocols appropriate for the current position of the patient support and/or set up the system to perform the appropriate imaging procedure. It should be appreciated that automatically selecting the appropriate imaging protocol(s) and/or performing other automatic setup activities may be performed based on the location and/or configuration of other components of the detection system, as these aspects are not limited in this respect.

In act 318, auto-tuning of the RF coil may be performed. Some embodiments may include functionality for automatically detecting the type of connected RF coil, and may perform automatic tuning of the RF coil based at least in part on the detected specific type of connected RF coil information. Other implementations may not include functionality for automatically detecting the type of RF coil connected, and may perform automatic tuning of the RF coil based at least in part on manually entered information regarding the type of coil currently connected.

Automatic detection of the type of connected RF coil may be achieved in any suitable manner. For example, the type of RF coil connected may be based at least in part on wiring in the connector of the coil. As another example, a programmable memory device (e.g., EPROM) programmed with configuration information for the coil may be included as part of the coil, and the configuration information may be downloaded to the low-field MRI system when the coil is connected or at some other time after the coil is connected. The configuration information may include information identifying the RF coil and any other suitable information to facilitate configuration and/or calibration of the RF coil. For example, as described above, information about the field of view (FOV) of the coil, the frequency range of the coil, the power scaling of the coil, calibration data of the coil, or any other suitable information may be stored on the storage device and may be used to automatically tune the RF coil when transmitted to the low-field MRI system. As yet another example, the connected RF coil may include an RFID tag that identifies the RF coil as a particular type, and the type of coil may be identified by the low-field MRI system based at least in part on the RFID tag. The RFID tag may store and provide other information about the corresponding coil, such as any of the information described above. It should be understood that any type of device capable of storing information that is actively or passively accessible may be used, as these aspects are not limited in this respect.

Various aspects of automatic RF coil configuration may be performed based at least in part on data collected during a configuration process. For example, some embodiments may be configured to automatically detect the field of view and/or position of the patient prior to imaging by performing a test localizer pulse sequence and analyzing the MR response. To speed up the configuration process, in some embodiments, such a sequence of locator pulses may be performed before the magnet is fully heated, as described above. Appropriate adjustments can then be made to the patient and/or components of the low-field MRI system while the magnet is heating. However, such a pulse sequence may be applied after the magnet is heated, as this technique is not limited to use at any particular point in time.

According to some embodiments, the field of view and/or the center position is determined by acquiring a low resolution image to find the spatial extent of the object. Alternatively, the spatial extent may be obtained by acquiring a signal projection through the object. The system may be adjusted based on detecting where the object is located within the field of view, or a warning message may be provided if the object is outside the field of view to an extent that it cannot be adjusted or compensated for. The field of view and/or the center position may be used to obtain one or more fast scout images. The scout image may be used in a variety of ways to facilitate the imaging process. For example, a user may select a scan volume by dragging a box over a desired portion of the scan image or otherwise annotating the scout image to indicate a desired region to perform image acquisition. Alternatively, the user may zoom in or out (e.g., using a zoom tool, using a gesture on a touch screen, etc.) to select a scan volume to perform a higher or full resolution scan. According to some embodiments, a scout image may be displayed, wherein the position of one or more receiving coils is superimposed on the image. This information may be used to determine whether the patient is within the field of view to satisfactorily image the target portion of the anatomy.

According to some embodiments, other techniques may be used, such as using one or more optical cameras to determine spatial extent. Information obtained from one or more optical cameras can be used to assess where the patient is located and whether the patient is positioned in a manner suitable for imaging.

Returning to the process of fig. 3, in act 320, automatic shimming is performed. As described above, some low-field MRI systems used with the techniques described herein include one or more shim coils that can be energized to adjust B₀A field to account for inhomogeneities in the field. In some embodiments including shim coils, B may be improved in a similar manner by selectively activating shim coils₀Uniformity of field to perform B₀And (4) calibrating the field. According to some embodiments, one or more sensors are used to determine system characteristics (e.g., uniformity of the magnetic field, stability of the system) and/or characteristics of ambient noise, and information from the sensors may be used to determine the magnetic field by adjusting operating parameters of the magnet (including but not limited to adjusting B)₀The magnet, the selection of one or more shim coils to operate, and/or the selection of operating parameters of one or more shim coils) to tune the magnetic field.

In some embodiments, the automatic shimming is performed only after the magnet has been fully heated. In other embodiments, automatic shimming is performed during the heating process to acquire images before the magnet is fully heated as needed. A predetermined sequence or response to B may be used₀The measurement of the field to perform automatic shimming, as aspects of the invention are not limited in this respect. In addition, automatic shimming may be performed at start-up and/or at any other suitable interval when the low-field MRI system is in use. Dynamic adjustment of B by using automatic shimming periodically or continuously during operation₀The field may facilitate the acquisition of higher quality images in environments with varying characteristics, noise levels, and/or in situations where the magnet temperature fluctuates, either during operation or because the magnet does not reach thermal equilibrium.

According to some embodiments, a low-field MRI system may include: a field sensor arranged to obtain local magnetic field measurements in conjunction with a magnetic field generated by the low-field MRI system and/or a magnetic field in the environment. These magnetic field measurements may be used to dynamically adjust various properties, characteristics, and/or parameters of the low-field MRI system to improve the performance of the system. For example, a network of spatially distributed field sensors may be arranged at known locations in space to enable real-time characterization of the magnetic field produced by a low-field MRI system. The sensor network is capable of measuring the local magnetic field of the low-field MRI system to provide information that facilitates any number of adjustments or modifications to the system, some examples of which are described in further detail below. Any type of sensor capable of measuring the magnetic field of interest may be used. Since concepts related to using magnetic field measurements are not limited to the type, number, or method of providing sensors, such sensors may be integrated within one or more laminates, or may be provided separately.

According to some embodiments, the measurement provided by the sensor network provides information that facilitates establishing appropriate shimming to provide B with a desired intensity and uniformity₀Information of the field. As described above, any desired number of shim coils of any geometry and arrangement may be integrated in the laminate, alone or in combination with other magnetic components, such that different combinations of shim coils may be selectively operated and/or operated at desired power levels. Thus, when a low-field MRI system is operating in a particular environment, measurements from the field sensor network may be used to characterize the magnetic resonance signal represented by, for example, B₀A magnetic field generated by a magnet and/or gradient coils to determine what combination of shim coils should be selected for operation and/or at what power level to operate the selected shim coils to affect the magnetic field such that the low-field MRI system produces B with a desired strength and uniformity₀A field. This capability facilitates the deployment of a generally portable, transportable and/or transportable system, since B can be performed for a given location using the system₀And (6) field calibration.

According to some embodiments, measurements from the field sensor network may be used to perform dynamic shimming during operation of the system. For example, the sensor network may measure the magnetic field generated by the low-field MRI system during operation to provide information thatInformation may be used to dynamically adjust (e.g., in conjunction with operating the system in real-time, near real-time, or otherwise) one or more shim coils and/or to operate shim coils of different combinations (e.g., by operating one or more additional shim coils or stopping operation of one or more shim coils) such that the magnetic field produced by the low-field MRI system has or is closer to having desired or expected characteristics (e.g., producing the resulting B at a desired or closer to a desired field strength and homogeneity)₀A field). Measurements from the field sensor network may also be used to inform the operator of the magnetic field quality (e.g., B)₀Field, gradient field, etc.) may not meet the desired criteria or metrics. For example, if B is being generated₀The operator should be warned that the field fails to meet certain requirements regarding field strength and/or homogeneity.

According to some embodiments, measurements from the sensor network may be used to guide and/or correct the reconstruction and/or processing of MR data obtained from operating the low-field MRI scanner. In particular, the actual spatio-temporal magnetic field pattern obtained by the sensor network may be used as knowledge when reconstructing an image from acquired MR data. Thus, a suitable image may be reconstructed even in the presence of field inhomogeneities that are otherwise unsatisfactory for acquiring data and/or generating an image. Accordingly, techniques that use field sensor data to assist in image reconstruction help in obtaining improved images in some situations and enable low-field MRI to be performed in environments and/or situations where field strength and/or homogeneity is degraded.

According to some embodiments, the field sensor network may be used to measure and quantify system performance (e.g., eddy currents, system delays, timing, etc.) and/or may be used to facilitate gradient waveform design based on measured local magnetic fields, etc. It should be appreciated that the measurements obtained from the field sensor network may be used in any other manner to facilitate performing low-field MRI, as these aspects are not limited in this respect. In a generally portable, transportable, or transportable system, the environment in which the MRI system is deployed may be generally unknown, unshielded, and generally uncontrolled. Thus, the ability to characterize the magnetic field produced by a low-field MRI system in a given particular environment (magnetic and other) facilitates the ability to deploy such systems in a wide range of environments and situations, allowing the systems to be optimized for the given environment.

According to some embodiments, one or more measurements made by the low-field MRI system may be used in addition to or instead of the field sensor network, as described above. Replacing the use of MR-based measurements by the low-field MRI system with measurements by the field sensor network may simplify the design of the low-field MRI system and enable the low-field MRI system to be produced at reduced cost.

In some embodiments, the low-field MRI system may send diagnostic information to a centralized location (e.g., one or more networked computers associated with database 550) before determining that the system is ready to image the patient. In this manner, the low-field MRI system may be connected to the cloud to exchange information prior to imaging or at any time during setup, configuration, and/or operation. The transmitted diagnostic information may be analyzed at a centralized location and if it is determined that the low-field MRI system is functioning properly, a message may be sent back to the system to inform the user that the system is ready for imaging. However, if a problem is detected in response to analyzing the communicated information, information indicating that the system may have an operational problem may be sent back to the system. The information returned to the low-field MRI system may take any form, including but not limited to a simple ready/not ready indication, and a detailed analysis of the detected problem if it is found. In some embodiments, the information sent back to the low-field MRI system only indicates that the low-field MRI system requires maintenance.

According to some embodiments, the provided diagnostic information may include a current version of software installed on the low-field MRI system. From this information, a determination may be made that the MRI system is operating using the latest version of software. If it is determined that the current version of software installed on the low-field MRI system is not up-to-date, the information sent back to the MRI system may include an indication that the software should be updated. In some embodiments, the ability to operate a low-field MRI system may be limited based on the importance of the software update. According to some embodiments, a latest version of software may be downloaded from a cloud-connected computer to dynamically update a system upon detecting that the system is not using the latest version of software and/or otherwise operating with old and/or out-of-date software.

Some embodiments may be configured to provide dynamic configuration of an MRI system by enabling a console to adjust the manner in which images of a desired quality and resolution are generated using an MRI sequence. Conventional MRI consoles typically operate by having a user select a preprogrammed MRI pulse sequence, which is then used to acquire MR data that is processed to reconstruct one or more images. The doctor may then interpret the resulting image or images. The inventors have recognized and appreciated that operating an MRI system using a pre-programmed MRI pulse sequence may not be effective in producing images of a desired quality. Thus, in some embodiments, the user may specify the type of image to be acquired, and the console may be responsible for deciding on initial imaging parameters, optionally updating the parameters as the scan progresses to provide a desired type of image based on analyzing the received MR data. Dynamically adjusting imaging parameters based on computational feedback facilitates the development of "push-button" MRI systems, where a user may select a desired image or application, and the MRI system may decide a set of imaging parameters for acquiring the desired image, which may be dynamically optimized based on MR data obtained during acquisition.

Returning to the process of FIG. 3, in act 322, an external electronic device (e.g., external electronic device 585 shown in FIG. 5) may be detected. The inventors have recognized that the use of a low-field MRI system allows patients, medical practitioners, and others to have and use electronics 460 in close proximity to the MRI system without the safety issues that can arise when such equipment is located in close proximity to a high-field MRI system. One such external electronic device is a wearable electronic device (e.g., a smart watch, sensor, monitor, etc.) that may be securely used in low-field environments. The wearable electronic device may store and/or detect patient data that can facilitate the acquisition of images using a low-field MRI system. Accordingly, some embodiments automatically detect the presence of such electronic devices and download patient data (e.g., heart rate, breathing rate, height, weight, age, patient identifier, etc.) to the low-field MRI system for use in acquiring imaging data. For example, the patient data may be used to gate or modify one or more data acquisition parameters (e.g., pulse sequences) to customize the data acquisition process based on patient-specific data for a particular individual.

The patient data may also be used to select an appropriate pulse sequence or other operating parameter of the low-field MRI system from a set of possible pulse sequences or operating parameters. Alternatively, the patient data may be used for any other purpose to improve imaging by the low-field MRI system. For example, heart rate data and/or respiration rate data received from a wearable electronic device may be used to reduce and/or correct motion artifacts caused by patient motion. Additionally, physiological data such as heart rate or respiratory rate may be used to provide synchronization information for the imaging process. The wearable electronic device may be detected in any suitable manner using any suitable wireless discovery technology, examples of which are known.

The wearable device may include an RFID tag that includes patient data such as demographic information, health information about the patient (e.g., whether the patient has a pacemaker, an implant, etc.), information about the imaging protocol of the patient, and the like. This information may be used by the system to automatically prepare and/or set up the system to perform imaging according to the appropriate protocol. For example, the system may perform one or more checks to ensure that the system is properly configured (e.g., the correct transmit/receive coils are connected to the system, the couch is in place, etc.) for the desired imaging procedure, may select an appropriate pulse sequence, automatically configure one or more parameters of the system, prepare to acquire one or more scout images, and/or automatically perform any other suitable procedure to prepare to acquire the image(s) according to the desired protocol. The information obtained from the RFID tag may include any other information including, but not limited to, contrast media type, contrast media amount, etc., the destination of the acquired image (e.g., PACS, cloud, remote radiologist, centralized server, etc.), and/or any other information that facilitates the imaging process.

It should be understood that any of the above information may be obtained by the system using other techniques, such as scanning a barcode or hospital label, or obtaining information available on the patient's mobile device (e.g., a smartphone or wearable device), as automatically obtaining information about the patient and/or the desired imaging procedure is not limited to using any particular technique. For example, a patient's mobile device (e.g., smartphone, wearable device, etc.) may include health information, diagnostic information, or other information that may be accessed and utilized to obtain information that may inform automatically setting aspects of an imaging protocol and/or imaging procedure.

The inventors have also recognized that some external electronics (e.g., a mobile computing device) may be used to control various operational aspects of the low-field MRI system. For example, rather than requiring a healthcare professional to control the low-field MRI system from a dedicated console, some embodiments allow an external electronic device, such as a smartphone or tablet computer, to control the operation of the low-field MRI system. The electronics may be programmed with control instructions (e.g., using a control application) that, when within range of the low-field MRI system, enable a user of the electronics to control at least some operations of the system. Thus, some low-field MRI systems used in accordance with some techniques described herein may be configured to automatically detect the presence of external electronics that may be used to remotely control at least some operations of the low-field MRI system. Additionally, one or more applications installed on the external electronic device may also include instructions that enable a healthcare professional to use the device to access and view one or more images stored on the PACS 560.

As noted above, the imaging process may be controlled using any number of local or remote devices, including the user's mobile device, a computer local to the remote radiologist, a local computer at the system and/or an integrated computer, etc. The inventors have realized that whatever device is used, user interface functionality may be implemented to facilitate the inspection process. For example, during an examination procedure, a region of interest may be selected via one or more scout images or via one or more higher resolution images, and additional scans may be automatically performed to acquire additional images corresponding to the selected region of interest. According to some embodiments, to assist the local user and/or the remote radiologist, previously acquired images of the subject may be displayed and/or reference images of expected or healthy anatomy/tissue may be displayed. Previously acquired images may be used as comparisons to identify abnormal regions, monitor changes in the patient (e.g., to determine the efficacy of treatment), or otherwise provide diagnostic assistance. The reference image may be used to assist in identifying abnormal anatomical structures, abnormal tissue, and/or identifying any other condition that is expected to deviate from the reference image characterization.

The inventors also understand that automatic analysis of the obtained images can be performed to detect various events, occurrences, or conditions. For example, poor image quality in one or more regions may be detected and an appropriate pulse sequence obtained to acquire additional image data to fill in gaps, increase signal-to-noise ratio, and/or otherwise obtain higher quality image data and/or improve image quality in selected regions. As another example, the acquired images may be analyzed to detect when the target anatomy is not sufficiently captured in the acquired images and alert the user that additional imaging may need to be performed.

The above-described configuration operations of fig. 3 have been described primarily in the context of configuring a low-field MRI system during initial system startup. However, it should be understood that one or more of the configuration operations may additionally or alternatively be performed automatically during operation of the low-field MRI system. As an example, the temperature of the magnet may be monitored during system operation using a temperature sensor or by measuring the voltage of the magnet as described above. The magnet voltage/temperature may also be monitored during operation to assess whether components of the thermal management system (e.g., pumps, fans, etc.) are functioning properly. Additionally, one or more components of the thermal management system may be directly monitored during operation of the low-field MRI system to ensure that the components of the low-field MRI system are properly cooled as desired.

To reduce power consumption of the low-field MRI system during operation, a control application executing on a console of the system may monitor user activity. When no user activity is detected for a certain amount of time (e.g., 30 minutes, 1 hour), the low-field MRI system may automatically enter a low-power mode to reduce power consumption and/or operational burden on the components (which may shorten the useful life of the device). According to some embodiments, the low-field MRI system may have multiple low-power modes that represent different states of user inactivity, and the low-field MRI system may transition between the different low-power modes, rather than turning off completely when no user activity is detected. For example, a low-field MRI system may be configured to have three low-power modes, each corresponding to a different state that maintains the magnet at a desired power and temperature. Upon detecting user inactivity for a short period of time (e.g., 30 minutes), the magnet may automatically enter a "light" low power mode in which the current provided to the magnet is reduced slightly to reduce power consumption. If user inactivity is detected over a longer period of time (e.g., 1 hour), the magnet may automatically transition to a "medium" low power mode in which the current provided to the magnet is further reduced to consume less power. If user inactivity is detected for an even longer period of time (e.g., 4 hours), the magnet may automatically transition to a "deep" low power mode in which the current provided to the magnet is reduced even further to consume less power resources.

When the magnets cool in different low power modes, the components of the thermal management system (e.g., fans, pumps) may be adjusted accordingly. Although three different low power modes are described above, it should be understood that any suitable number of low power modes (including zero or one low power mode) may alternatively be used. Furthermore, the time periods given above are merely exemplary, and any time period may be used as a basis for triggering a transition to a low power mode. Further, as the automatic transition to the low power mode is not limited to any particular type of trigger, other aspects of the system may be monitored and/or other events may be used to trigger the transition to the low power mode.

According to some embodiments, a user may interact with the control application to place the magnet in a low power mode without relying on an automated process (e.g., detection of user inactivity). A return to normal operation of the low-field MRI system from the low-power mode may be initiated in response to detection of user activity, for example, via a control application on the console (e.g., a user is engaged in a user interface control on the console), via an external electronic device in communication with the low-field MRI system, or in any other suitable manner.

The inventors have realized that if B is₀The polarity of the field remains constant, then objects in the environment near the low-field MRI system may become magnetized over time, and the magnetization of the objects in the environment may cause B₀Distortions (e.g., offsets) in the field, resulting in poor image quality. Demagnetizing the environmental object may comprise performing a demagnetization process in which the magnetization of the object is reduced. Some embodiments relate to reducing the source of magnetization rather than dealing with its effects. For example, some low-field MRI systems may be configured to switch B occasionally (e.g., once per day)₀The polarity of the field to prevent magnetization of objects in the surrounding environment. At periodic switching of B₀In the embodiment of the field polarity, B may be considered in the automatic shimming process₀The current polarity of the field to enable accurate shimming.

According to some embodiments, ferromagnetic components are used to increase B₀Field strength of magnet without additional power or with reduced amount of power to produce the same B₀A field. Such ferromagnetic components may become magnetized as a result of operating the low-field MRI system, and may be magnetized relatively quickly, thereby interfering with B in an undesirable manner (i.e., other than as intended)₀A field. Thus, the degaussing technique described above (e.g., switch B)₀Polarity of the magnet) can be used to prevent magnetization of the ferromagnetic componentInfluence of land by B₀The field, thereby adversely affecting the operation of the low-field MRI system. As noted above, low-field MRI facilitates the design and development of MRI systems, which is generally not feasible with high-field MRI, e.g., MRI systems that have relatively low cost, reduced footprint, and/or are generally portable or transportable.

Having thus described several aspects and embodiments of the technology set forth in the disclosure, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be within the spirit and scope of the technology described herein. For example, various other means and/or structures for performing the function and/or obtaining the result and/or one or more of the advantages described herein will be readily apparent to those of ordinary skill in the art, and each such variation and/or modification is considered to be within the scope of the embodiments described herein. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, embodiments of the invention may be practiced otherwise than as specifically described. In addition, any combination of two or more features, systems, articles, materials, apparatus, and/or methods described herein is included within the scope of the present disclosure if such features, systems, articles, materials, apparatus, and/or methods are not mutually inconsistent.

The above-described embodiments may be implemented in any of a number of ways. One or more aspects and implementations of the present disclosure relating to the performance of a process or method may utilize program instructions that are executable by an apparatus (e.g., a computer, processor, or other device) to perform or control the performance of a process or method. In this regard, the various inventive concepts may be embodied as a computer-readable storage medium (or multiple computer-readable storage media) (e.g., a computer memory, one or more floppy disks, compact disks, optical disks, magnetic tapes, flash memories, circuit configurations in field programmable gate arrays or other semiconductor devices, or other tangible computer storage medium) encoded with one or more programs that, when executed on one or more computers or other processors, perform methods that implement one or more of the various embodiments described above. The computer-readable medium or media may be transportable, such that the one or more programs stored thereon can be loaded onto one or more different computers or other processors to implement various ones of the above-described aspects. In some implementations, the computer-readable medium may be a non-transitory medium.

The terms "program" or "software" are used herein in a generic sense to refer to any type of computer code or set of computer-executable instructions that can be employed to program a computer or other processor to implement various aspects, as discussed above. In addition, it should be understood that according to one aspect, one or more computer programs that when executed perform methods of the present disclosure need not reside on a single computer or processor, but may be distributed in a modular fashion amongst a number of different computers or processors to implement various aspects of the present disclosure.

Computer-executable instructions may be in many forms, such as program modules, executed by one or more computers or other devices. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Typically, the functionality of the program modules may be combined or distributed as desired in various embodiments.

In addition, the data structures may be stored in any suitable form on a computer readable medium. For simplicity of illustration, the data structure may be shown with fields that are related by location in the data structure. Likewise, such relationships can be implemented by allocating storage for fields in a computer-readable medium having locations that convey relationships between the fields. However, any suitable mechanism (including by using pointers, tags, or other mechanisms that establish relationships between data elements) may be used to establish relationships between information in fields of a data structure.

When implemented in software, the software code can be executed on any suitable processor or collection of processors, whether disposed in a single computer or distributed among multiple computers.

Further, it should be appreciated that a computer may be implemented in any of a variety of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer, as non-limiting examples. Additionally, a computer may be embedded in a device not normally considered a computer but with suitable processing capabilities, including a Personal Digital Assistant (PDA), a smart phone, or any other suitable portable or fixed electronic device.

In addition, a computer may have one or more input and output devices. These devices may be used, inter alia, to present a user interface. Examples of output devices that may be used to provide a user interface include: a printer or display screen for visually presenting output and a speaker or other sound generating device for audibly presenting output. Examples of input devices that may be used for the user interface include keyboards, and pointing devices, such as mice, touch pads, and digitizing tablets. As another example, a computer may receive input information through speech recognition or in other audible format.

Such computers may be interconnected by one or more networks IN any suitable form, including local or wide area networks (e.g., enterprise networks) and Intelligent Networks (INs) or the internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol and may include wireless networks, wired networks, or fiber optic networks.

Further, as described, some aspects may be embodied as one or more methods. The actions performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed which perform acts in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

All definitions, as defined and used herein, should be understood to govern dictionary definitions, definitions in documents incorporated by reference, and/or ordinary meanings of the defined terms.

The indefinite articles "a" and "an" as used herein in the specification and the claims are to be understood as meaning "at least one" unless clearly indicated to the contrary.

The phrase "and/or" as used herein in the specification and claims should be understood to mean "either or both" (and/or) "of the elements so combined, i.e., elements that exist in some cases combined and in other cases separately. A plurality of elements listed with "and/or" should be interpreted in the same way, i.e. "one or more" of the elements so combined. In addition to elements specifically identified by the "and/or" clause, other elements may optionally be present, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, when used in conjunction with an open-ended language such as "comprising," references to "a and/or B (a and/or B)" may refer in one embodiment to a only (optionally including elements other than B); in another embodiment to B only (optionally including elements other than a); in another embodiment to a and B (optionally including other elements), and the like.

As used herein in the specification and claims, the phrase "at least one" with respect to a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including each and at least one of each element specifically listed in the list of elements, and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified in the list of elements referred to by the phrase "at least one" whether related or unrelated to those elements specifically identified. Thus, by way of non-limiting example, "at least one of A and B (or, equivalently," at least one of A or B (or, equivalently, "at least one of A and/or B (or, equivalently)" at least one of A and/or B ") can refer in one embodiment to: at least one, optionally including more than one, a, B is absent (and optionally including elements other than B); in another embodiment, refers to: at least one, optionally including more than one, B, a is absent (and optionally including elements other than a); in yet another embodiment, refers to: at least one, optionally including more than one, a and at least one, optionally including more than one, B (and optionally including other elements), and the like.

Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. As used herein, "comprising," "including," or "having," "containing," "involving," and variations thereof, is meant to encompass the items listed thereafter and equivalents thereof as well as additional items.

In the claims and in the above description, all transitional phrases such as "comprising", "including", "carrying", "having", "containing", "involving", "holding", "consisting of … … (compounded of)" and the like are to be understood as open-ended, i.e. to mean including but not limited to. The transitional phrases "consisting of" and "consisting essentially of" are, respectively, closed or semi-closed transitional phrases.

Claims

1. A method of operating a Magnetic Resonance Imaging (MRI) system comprising B₀A magnet and a cooling component configured to be cooled from the B during operation using one or more water-based or air-based cooling components₀At least one thermal management component that the magnet transfers heat away, the method comprising:

using a power supply to said B₀The magnet provides operating power;

energizing the MRI system, the energizing comprising:

monitoring the B using temperature sensors and/or voltage measuring means₀Temperature of the magnet to determine said B₀The current temperature of the magnet; and

when said B is₀Operating the at least one thermal management component below an operational capacity in response to the occurrence of at least one event to reduce the B when the current temperature of the magnet is below a first threshold temperature value₀A time required for a magnet to be ready for imaging, wherein the at least one event includes powering on the MRI system;

wherein the one or more water-based or air-based cooling components are configured to be driven from the B during operation₀The magnet transfers heat away; and

after the MRI system is powered on, at least one magnetic resonance imaging image is acquired using the MRI system.

2. The method of claim 1, wherein the B is monitored₀The temperature of the magnet includes monitoring the temperature using a temperature sensor.

3. The method of claim 1, wherein the B is monitored₀The temperature of the magnet includes measuring with the voltage measuring part and B₀The voltage associated with the magnet.

4. The method of claim 1, wherein the first threshold temperature value corresponds to the B₀Thermal equilibrium of magnet and/or B₀The field is stabilized.

5. The method of claim 1, further comprising: operating the B with a reduced amount of current when operating the at least one thermal management component at less than operational capacity₀A magnet to reduce power consumption in the low power mode.

6. The method of claim 1, further comprising determining fluctuations in at least one parameter of the magnetic resonance imaging system, and wherein acquiring at least one image comprises compensating for the determined fluctuations in the at least one parameter.

7. The method of claim 6, wherein the at least one parameter is the B₀Larmor frequency of magnet and/or by said B₀B produced by magnet₀Uniformity of the field.

8. The method of claim 6, wherein determining the fluctuation of the at least one parameter comprises: based at least in part on B₀The current temperature of the magnet determines the fluctuations.

9. The method of claim 8, wherein the B is monitored₀The temperature of the magnet includes measuring with the voltage measuring part and B₀A voltage associated with the magnet, and wherein determining the fluctuation of the at least one parameter comprises: based at least in part on measured B₀The voltage of the magnet determines the fluctuation.

10. The method of claim 1, wherein the magnetic resonance imaging system further comprises at least one gradient coil, and wherein the method further comprises: modifying an operating state of the at least one gradient coil in response to the occurrence of the at least one event.

11. The method of claim 10, wherein modifying the operating state of the at least one gradient coil comprises: operating power is provided to the at least one gradient coil.

12. The method of claim 10, wherein modifying the operating state of the at least one gradient coil comprises: reducing operating power provided to the at least one gradient coil.

13. The method of claim 1The method also comprises the following steps: operating said B₀Magnet to produce B suitable for low field magnetic resonance imaging₀At least a portion of the field.

14. A magnetic resonance imaging, MRI, system comprising:

B₀a magnet configured to provide B₀At least a portion of a field;

at least one thermal management component configured to use one or more water-based or air-based cooling components to remove moisture from the B during operation₀The magnet transfers heat away;

a temperature sensor and/or a voltage measurement component configured to monitor the B₀The temperature of the magnet; and

at least one processor programmed to:

during powering up of the MRI system:

obtaining the B using the temperature sensor and/or voltage measuring part₀The current temperature of the magnet; and

when said B is₀Operating the at least one thermal management component below an operational capacity in response to the occurrence of at least one event to reduce the B when the current temperature of the magnet is below a first threshold temperature value₀A magnet is ready for a time required for imaging, and wherein the one or more water-based or air-based cooling components are configured to be driven from the B during operation₀The magnet transfers heat away, wherein the at least one event includes energizing the MRI system; and

after the MRI system is powered on, the MRI system is caused to acquire at least one magnetic resonance imaging image.

15. The magnetic resonance imaging MRI system of claim 14, further comprising at least one gradient coil, and wherein the at least one processor is further programmed to be based at least in part on the B₀The current temperature of the magnet controls the operating state of the at least one gradient coil.

16. The magnetic resonance imaging MRI system of claim 14, further comprising being configured to provide B₁At least one radio frequency coil of a field, and wherein the at least one processor is further programmed to control an operational state of the at least one radio frequency coil based at least in part on a current temperature of the magnet.

17. The magnetic resonance imaging MRI system of claim 14, further comprising at least one shim coil, and wherein the at least one processor is further programmed to be based at least in part on the B₀The current temperature of the magnet controls the operating state of the at least one shim coil.

18. The magnetic resonance imaging MRI system of claim 14, wherein B₀The magnet is configured to provide B suitable for low-field magnetic resonance imaging₀A field.